The prior art already comprises a cigarette-filter making apparatus wherein, after the formation of a continuous cigarette-filter string the latter is cut up by severing means into individual filter lengths which are delivered individually to a circumferentially longitudinally grooved dispensing cylinder for subsequent lateral discharge to a conveyor belt. In this arrangement the filter string is checked forwardly of the severing station by means of a quality control system which actuates a pneumatically operated ejector device arranged partly within the interior of the hollow cylinder. The ejector device comprises a stationary part extending over a portion of the inner circumferential wall of the cylinder in sealed engagement therewith to form a chamber which communicates via radial bores with a portion of the receiving grooves, said stationary part being adapted to be alternatively connected with low or high pressure sources. Switchover from low to high pressure source connection and vice versa is controlled by the quality control device in such a fashion that in the presence of perfect filter strings a partial vacuum or low pressure, and for faulty filter strings a high pressure for ejecting the faulty filter lengths is applied to the work-receiving grooves via said chamber inside the cylinder which communicates therewith. However, this existing apparatus has the disadvantages of a complicated and expensive construction, presenting a comparatively large number of parts which are subject to wear and being unsuitable for the aimed elimination of only a few individual filter sections.